CM is getting excited. Like all fathers he is becoming his child. “Essen essen essen” (“food food food”) seems to be his son’s favourite occupation this week, so CM’s response as he arrives in the workshop is “Fraesen, fraesen, fraesen!” (“milling, milling, milling!”) which, spoken suitably childlike, sounds about the same.

Which was precisely the task for today. After replacing one of the toothed belts that got too warm from some building process in the early stages of RunCNC, so our round gears are now round and we can finally assemble the geared extruder that is high on the wish list.

But for this we need more electronics, and more electronics is always a bit hard, so we want to make our own circuit boards, so we have put together the simplest of all mills. CM has been drilling wood and greasing nice threaded rods, CH has been fiddling with some stepper driver boards. My role has been a bit slow. But today I got to write a program with which to create some G-code that would mill out the position in the working surface that the circuit board lies in as the copper is being milled away. Which worked all very nicely except that I forgot that the first round takes off one millimeter outside the tool path as well. Oops. So our boards will need to be wedged in somehow. Double sided tape is pretty impressive stuff.

But try as I might to break stuff, the wonderful “basteln” has paid off and the first proper milling has taken place.

The first cut! Milling through the wood word surface, a perfectly straight line!

We pumped up the voltage on the Proxxon tool to 18V instead of the normal 12V, raised the feedrate and the tool happily dug through the wooden working surface.The Woody Miller is in great shape.

Now we have it set up, the first circuit board is about to get milled. Time is on our side.

The traces have been etched (so to speak), now we have inserted the drillbit and are setting the zero point.

The milling goes smoothly, the traces separated off from the rest of the copper. We are a bit worried by the occasional copper splinter that crosses the insulating gaps. But they seem not to turn up too often.

The first PCB. Traces fine, holes were drilled a touch too shallow so they do not go through. But close enough!

Now we have the first PCB made, the next ones will not block us too long. Some teething issues with the “tool change” height being zero, so the drill bit traversed the PCB just too low and ended up snapped off. Things are looking good.

This is a very nice position to be in. We can build objects and electronics as we want them, within certain limits of exactness. There is a whole swathe of programs and systems out there to build strange things. People doing strange things and sharing them, encouraging us to do the same.